[tthisk]

Yes this quote got me cringing, these things are definitely not 'simple'. The post's title is also presumptuous. While Haskell is a brilliantly elegant language, by capturing abstractions at a high level (i.e. category theory). This is also it's fallacy, these abstraction are inherently hard to understand because, well, they are so abstract. When writing most software in the real world we need to be pragmatic to be able to recruit people to actually write that software. So will Haskell take over all software engineering, I don't think so. Fortunately we can, and are already learning a lot from ideas introduced by Haskell.

[UK-Al05]

They are simple, but not easy learn.

Lambda calculus is simple. Incredibly simple. But trying use lamda calculus to do anything with is hard.